If she signed the form appointing you to be her representative, you should be able to order the notes on her behalf.
There is a special permission to sign if yuo are asking a company to get the CAIPS notes for you.
My wife is the applicant, and I am her representative. I've ordered CAIPS notes twice, through a company, and each time my wife (the applicant) signed the permission form. It is a special permission form allowing the company to access the CAIPS notes only, and does not override the form appointing me a representative.
If you are applying for the CAIPS notes directly, I believe that the representative signs the request. It might be wise to include a copy of the form designating the representative.